Abstract:Based on the surface observation data of 192 meteorological stations during 1961-2008 in South China， the climatic characteristics and variations of haze days and fog days in South China were studied by using statistical diagnostic methods， such as linear regression analysis， Mann Kendall test and the computation of trend coefficients. The results showed that haze days were more in the Pearl River Delta area，northwest areas of Guangdong and northeast areas of Guangxi, the fewest areas of hazes were in Hainan. There were three more fog regions in South China: the middle and western area of Hainan, northeast area of Guangxi and Guangdong, the annual mean fog days showed a decreasing trend from inland to coastal regions. The annual haze days in South China have increased obviously at a mean rate of 5.8 d/10a， it was more than that of the country mean （3.19 d/10a） obviously. There were obvious regional differences in the variable trend of annual haze days in South China， the increasing trends of haze days were obvious in the Pearl River Delta area， northwest areas of Guangdong, the middle and northeast areas of Guangxi, the increasing center was in Shenzhen (38.8 d/10a). The annual fog days in South China have decreased obviously at a mean rate of -0.8 d/10a， it displayed significant regional differences in South China. The fog days have decreased obviously in eastern and southern Guangdong, western and northern Guangxi, most parts of Hainan. The largest decreasing rate was in Baoting of Hainan （-16.8 d/10a）， the largest increasing rate was in Baisha of Hainan (20.7 d/10a). The annual mean haze days had an abrupt change in 1989, fog days had an abrupt change in 1995.